Viacom is understood to be close to beating out competition from competitor JCDecaux to secure the deal, which is believed to be worth £100m a year over a period of eight years.
The pitch was reduced to a last-ditch fight between the two outdoor companies in October last year and the outcome means that Viacom Outdoor will continue to control outdoor advertising across the network when its current contract expires in August this year.
The London Underground contract, known as the London Underground Limited portfolio, is one of the largest outdoor contracts in the world and encompasses cross-track platform sites, ranging from 16 to 96-sheet sizes, station corridor posters, and escalator and train panels.
The primary shortlist for the business included Scottish Media Group's Primesight, US-owned Clear Channel, Spanish outdoor firm Cemusa and Maiden Outdoor through its Insight Outdoor partnership.
Speaking at anonoucement of the tender, Chris Townsend, TfL's director of group marketing: said:"Against the backdrop of a buoyant outdoor market, we are confident that TfL will achieve unprecedented value for the new contracts, maximising revenues from our flagship advertising estates."
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